Improvement in metal-bending machines



-. C. CHAPMAN.

MetaL Bending Machine." No. 160,647 Patentd Marc1h9,1875.

FIGA.

WITNESSES.

INVENTOR.

THE GRAPHIC COPHOTOFLITH-SQBUH PLAG I a S ATES PA'IEN FFIGE.

JOHN G. CHAPMAN, OF PASSAIO, NEW JERSEY.

IMPROVEMENT IN METALBENDING MACHINES.

Specification forming part of Letters Patent No. 160,647; dated March 9,1875; application filed September 28, 1874.

To all "whom it may concern:

Be it known that I, JOHN G. CHAPMAN, of Passaic, in the county ofPassaic and State of New Jersey, have invented certain Improvements inMetal-Bending Machines, of which the following is a specification:

This invention pertains to certain improvements in machines for bendingplates or sheets of metal; and the invention consists in providing acentral support to each of the rolls,

at or near their centers, said supports being constructed of a saddlecarrying friction-rolls, and a truss-rod bearing on said saddle, wherebythe stiifness of the rolls is increased, and they are adapted to thebending of heavy plates of metal.

Figure 1 is a sectional elevation of the machine as would appear whenmade through the line as w in Fig. 2. Fig. 2 is a vertical sectionthrough the axis of the upper roll in the direction of its length. Fig.3 is a plan of the under side of the supporting frame or saddle. Fig. 4is an end view of the same. Fig. 5 is a view of the upper side of thesupporting-frame for the saddle over the top roll, the section at y y ofFig. 1.

Bending-machines, as commonly made, answer all the ordinary purposesrequired; but if plates of unusual thickness or width are to be bent,then the ordinary rolls fail to furnish the required stiffness, and areliable to spring at their centers to such a degree as to fail to performtheir work, or, if greatly strained, are often broken. But with myimprovement-s applied to any bending-machine the stiffness of the rollsmay be more than doubled, and the effi'ciency of the machine greatlyincreased.

The rolls are arranged and mounted as usual in said machines, and areshown at A A A The ends of each roll are supported by and are free torevolve in bearings, as at B, which are mounted in the frames 0. Thebearings of the top roll, and also one or both of the bottom rolls, aremade adjustable, and are regulated by the set-screws D, as seen inFig. 1. The frames are held in their proper positions apart by thestruts or bars E. At the middle of each roll, and in a line to resistthe greatest strain or deflection, is placed the supplemental hearing orsupport to the rolls, as at F, Figs. 1, 2, and 5, and as shown in detailand enlarged in Figs. 3 and 4:. Said support is composed of a saddle, asat F, and stay-rod, as at G, which hold in position two friction-rolls,F and F which bear upon the surface of the bending-rolls, and saidsaddles are held in position by the truss or tension rods G, whichextend across from one frame to the other, and are curved over in theform of an arch, as shown in Fig. 2, and are held in tension by ascrew-nut at one end, and may be used up to the breaking strain of therod.

By such an arrangement, when the rod G is under tension, and the saddleF, with its rolls, is held in position over the center of thebending-roll, thereby forming a strut between the trnss-rod and theroll, any tendency to deflection in the roll is'resisted by the rod G,and therefore the strength of the roll may be increased to a degreeequal to the tensile strength of the truss-rod Gr. Of course the samedegree of stiffness might be produced by increasing the size of therolls; but this will add greatly to the cost of the machine, as well asmake it very cumbersome,

but it also renders such a machine useless for bending small curves orcylinders.

It may also be observed that in such a machine, where the upper portionof the frame is not provided with the struts or bars E, to hold themapart, a movable strut, or two or more pieces, as at H, may beintroduced, with their ends bearing upon the inner sides of the frameabove the top roll, and against the ends of the saddle, so as to preventa pressure upon the shoulders of the roll, as seen in Figs. 2 and 5.

Having thus fully described my invention, I claim--- 1. The combinationof the support or sad die F, having friction-rolls F and rod G, with theframe of a metal-bending machine, to support the bendingrolls, asdescribed, and for the purposes set forth.

2. The combination, with the supports or saddles F, havingfriction-rolls, the truss-rod G, and the frame of a metal-bendingmachine, of the supplemental stays H, substantially as and for thepurpose described.

JOHN C. CHAPMAN.

Witnesses:

BOYD ELIOT,- L. M. OAPEN.

